Soluble highly branched glucose polymers and their method of production

ABSTRACT

The invention relates to soluble highly branched glucose polymers having a reducing sugar content of less than 1%, characterized in that they have a level of α-1,6 glucoside bonds greater than 10%, preferably of between 12 and 30%, a Mw value of between 0.35×10 5  and 2×10 5  daltons, and an osmolality having a value of between 1 and 15 mOsm/kg. The invention also relates to their method of production and their applications in the Paper-Carton, Textiles, Cosmetics, and particularly Pharmaceutical and Food industries, and still more particularly in the fields of enteral and parenteral nutrition, peritoneal dialysis as a glycemia inhibiting and/or regulating agent, as an energy source during physical activities and as a digestion regulating agent.

This application is a division of application Ser. No. 10/454,225, filedon Jun. 4, 2003 now U.S. Pat. No. 6,861,519, the entire contents ofwhich are hereby incorporated by reference.

The invention relates to soluble highly branched glucose polymers havinga reducing sugar content of less than 1% and having a remarkably highcontent of α-1,6 glucoside bonds, which is greater than 10%, for a verynarrow molecular weight distribution, which is between 0.3×10⁵ and 2×10⁵daltons, and a very low osmolality, which is between 1 and 15 mOsm/kg.

These soluble branched glucose polymers moreover have a low viscosityand an absence of retrogradation, even after cold storage after longperiods of time.

The invention also relates to a method for manufacturing said solublehighly branched glucose polymers.

It also relates to compositions comprising such soluble branched glucosepolymers which it is possible to use in numerous industrialapplications, and in particular in the food and especiallypharmaceutical industries.

The glucose polymers which are industrially accessible are in particularprepared by hydrolysis of natural or hybrid starches and of theirderivatives.

Standard starch hydrolyzates are thus produced by acid or enzymatichydrolysis of starch from cereals or tubers. They are in fact a mixtureof glucose and glucose polymers of extremely varied molecular weights.

These starch hydrolyzates (dextrins, maltodextrins, and the like) whichare produced in industry (with a certain Degree of Polymerization ormean DP) consist of a wide distribution of saccharides containing bothlinear structures (α-1,4 glucoside bonds) and branched structures (α-1,6glucoside bonds).

These starch hydrolyzates, and in particular the maltodextrins, are usedas a transporter or a filler, as a texturing agent, as a spray-dryingsupport, as a fat replacer, as a film-forming agent, as a freezingregulator, as an anticrystallizing agent, or for their nutritionalvalue.

It is moreover known to persons skilled in the art that the saccharidecomposition of maltodextrins determines both their physical andbiological properties.

Accordingly, their hygroscopicity, their fermentability in foodproducts, their viscosity, their sweetening character, their stability,their gelling character and their osmolality are criteria which areconventionally determined for their various fields of application.

Basic knowledge of the physicochemical behavior of these saccharidesthus leads to their being incorporated, for example, into drinks forathletes, liquid drinks with limited solubility, parenteral and enteralfluids or in foods for diabetics.

As a result, for these different applications, various physical andbiological properties are required.

It is for example known that the rate of absorption of these saccharidesis determined by the rate of gastric emptying and the rate of intestineadsorption, the regulation of which is provided by the osmolality ofsaid saccharides.

At the intestinal level, the maltodextrins are hydrolyzed by pancreaticα-amylase, which leads to their size being reduced to limit dextrins,and a number of enzymes linked to the intestinal mucous membrane(maltase, sucrase and α-dextrinase) continue to hydrolyze the linear andbranched saccharides to glucose.

While glucose easily crosses the intestinal barrier (passive diffusion),the same is not true of saccharides with a low DP. Accordingly, linearoligosaccharides will be adsorbed more quickly than branchedoligosaccharides, although maltose and maltotriose are absorbed morequickly than glucose.

The colon bacteria will ferment all the carbohydrates which are notadsorbed by the small intestine. Excessive fermentation by thesebacteria will result in intestinal disorders such as cramps andflatulence.

It is also known that the osmolality influences the rate ofabsorption/secretion of water in the small intestine. The higher theosmolality of a compound, the more it induces entry of fluid into theintestine and leads to serious stomach upsets (osmotic diarrhea), withconcomitant loss of fluid and of electrolytes.

The osmolality of a solution is equal to the quantity of moles dissolvedper kg of water, which implies that at the same concentration by dryweight, the osmolality of a conventional maltodextrin increases with adecrease in its DP.

In general, maltodextrins are well absorbed by the human body, but undermore extreme physical conditions, such as sports exercise or disease, abetter supply of carbohydrates should be provided.

For example, in athletes, a drink consumed during physical activitywhich requires a lot of effort should instantly provide the energy andthe water necessary to compensate for the loss of fluid throughperspiration.

It results from what has been stated above that a composition which isbalanced in relation to carbohydrates is essential in order to obtainsuch a result.

One solution which is conventionally proposed for the optimum drink isto choose short linear oligosaccharides with a DP of 3 to 6, since theyare absorbed at the highest rate, while retaining the osmolality at amoderate level, thus preventing the loss of fluids and side effects suchas diarrhea and cramps.

However, these compositions have the disadvantage of constituting energysources which are too instantly assimilated by the body, which resultsin difficulties in maintaining a constant energy supply over longperiods of time.

Patent application WO 95/22,562 thus proposes novel starch derivativesintended to supply energy for preparation of or after physical effort.

They are dextrins, characterized by their molecular weights of between15×10³ and 10⁷ daltons, and a degree of 1,6 glucoside branching ofbetween 2 and 8%, preferably between 3 and 7%, which ensures renewal ofthe energy reserves in the form of glycogen.

In their liquid form, these particular dextrins cross into the smallintestine after rapid gastric emptying. This route is moreover regulatedby the osmolality of said dextrins.

A high osmolality means here that the substances of low molecular weightbind to water, which make the transport of water and of nutrients intothe cell difficult. The osmolality of blood is about 300 mOsm/l, and,with the aim of facilitating the transport of nutrients, it is desirablefor the osmolality of the substance to be considerably below this value.

A dextrin according to WO 95/22,562, having an average molecular weightof about 720 000 and a degree of branching of about 4%, is described ashaving an osmolality of 20 mOsm/kg sol.

However, these dextrins are prepared by acid treatment of native starch,more particularly of potato starch, under high temperature conditions,i.e. 110 to 140° C., and in a reaction time of 1 to 15 hours, whichleads to a 1,6 degree of branching, which corresponds both to α-1,6 andβ-1,6 glucoside bonds.

These atypical glucoside bonds are not digested by the enzymatic systemsof the intestine, and can lead to the accumulation of indigestibleresidues which certain undesirable bacteria will assimilate.

In another field of application, maltodextrins are often added to drinksin order to increase their viscosity. However, in those containingalcohol, the supply of MD with a high DP can cause problems of stabilityof the mixture.

Another solution which consists in adding maltose or glucose leadsnevertheless to an additional sweet taste being given to the mixture,which is not always desirable. Furthermore, these small oligosaccharidescan serve as fermentation substrates for undesirable microorganisms.

The maltodextrins most suitable for this field of application musttherefore combine and balance the parameters of “nonsweetness”,viscosity and stability.

In the field of parenteral solutions, nutritive solutions are designedin order to maintain a patient in good health and provide them withnutrients when they cannot be fed via their normal digestive system.

Since the solutions are directly supplied by the venous route, they mustbe isotonic and the glucose supply is limited.

To provide a daily energy of 10 000 kJ, it is described in an articlefrom FOOD Science Technology of 1999, pp. 345–355 by MARCHAL et al.,that it would be necessary to infuse 14 liters of isotonic glucosesolution (5% weight/volume of glucose), which widely exceeds humancapacities.

The intake of more concentrated glucose or fructose solutions (10 to 20%weight/volume) is possible, but not for long periods.

It is possible to administer linear saccharides with a DP of between 2and 5, since these saccharides are hydrolyzed by maltases in the kidney,and the glucose released is then reabsorbed. Accordingly, the use ofshort linear oligosaccharides makes it possible to supply sufficientenergy in an isotonic solution, without overhydrating the patient.

Moreover, since linear oligosaccharides with a DP of less than 7 arestable in solution over long periods of time, it is conventionallychosen to vary the DP between 2 and 7 in order to make it possible toconstantly supply the patients, over these long periods, with allnecessary energy.

However, this solution is not completely satisfactory, and it onlyenvisages the exploitation of linear glucoside structures.

As for enteral nutrition, it involves drinks which may either beinjected orally, or administered via a tube into the stomach or thesmall intestine.

For these enteral fluids, the major problem is diarrhea, due to anexcessively high osmolality. In principle, the same solution as thatfound for athletes may also apply here.

Conventionally, maltodextrins containing a complex mixture of linear andbranched saccharides, with a DE of 10 to 20, are therefore used, butwithout however giving complete satisfaction.

Specialists in these fields of application seek the solution to thesetechnical problems in the production of branched structures derived fromstarch.

Amylopectin, the main constituent of starch, becomes organized aroundlinear α-1,4 bonds and α-1,6 bonds which become crosslinked therewith.Knowledge of the microstructures has demonstrated that these two typesof bond are not uniformly distributed, but that regions with very denseα-1,6 bonds coexist with regions consisting solely of α-1,4 bonds.

It has been proposed, in U.S. Pat. No. 4,840,807, or JP patentapplication 11/187,708, to extract only the regions with dense α-1,6bonds as source of slowly absorbed carbohydrates, since the α-1,6 bondsare more difficult to degrade than the α-1,4 bonds.

Two families of products have thus been developed. The first involveslimit dextrins prepared by degradation of the regions with α-1,4 bondswith an α-amylase alone, and dextrins prepared by degradation of theregions with α-1,4 bonds by the simultaneous action of an α-amylase anda β-amylase.

The resistance of these limit dextrins to human digestive enzymes makesit possible to use them to regulate digestion, but also to controlglycemia (application for diabetic diets). This effect is attributed toslowing of the rate of digestive adsorption.

However, these compounds have the disadvantage of having a very lowmolecular weight (between 10 000 and 55 000 daltons), which limits theirexploitation in other fields of application.

EP patent 207,676 teaches that, for use in continuous and ambulatoryperitoneal dialysis, starch hydrolyzates are preferred which form clearand colorless solutions at 10% in water, having Mw of 5×10³ to 10⁶daltons and a low polydispersity index or Ip.

This results in compositions which predominantly contain glucosepolymers of high molecular weight between 5×10³ and 5×10⁵ daltons),which do not contain or which contain very little glucose oroligosaccharides with a DP of less than or equal to 3, and no or verylittle glucose polymers with a Mw greater than 10⁶ daltons.

It can easily be understood for this application that monomers orpolymers of low molecular weight rapidly cross the peritoneal wall andare thus of no lasting benefit for the creation of an osmotic pressuregradient, and that polymers of very high molecular weight, which have noosmotic power, should be avoided and should even be prohibited sincethey are potentially dangerous if they happen to precipitate followingtheir retrogradation.

Peritoneal dialysis consists in introducing a dialysis solution into theperitoneal cavity by means of a catheter. After a certain period, anexchange of solutes occurs between the dialyzate and the blood. The useof a suitable osmotic agent allows drainage of excess water from theblood to the dialyzate.

The standard method in peritoneal dialysis for removing excess water(ultrafiltration) and of solutes from the body in case of renaldeficiency consisted in using a dialysis solution which has been madehypertonic in relation to the plasma by adding glucose as osmotic agent.The flow across an ideal semipermeable membrane is mainly determined bythe total number of particles of solute (osmolality) which are presentin the solution, independently of their size. By contrast, in the caseof a biological membrane such as the peritoneal membrane, the flowdepends solely on the solutes not crossing or only rarely crossing themembrane and is not therefore necessarily linked to the total osmolalityof the solution. Additionally, the capacity of the solutes to cross themembrane is characterized by the shape of the molecules and their ioniccharge, and by their size.

The choice of an ideal osmotic agent is delicate: the latter shouldallow an osmotic gradient so as to displace the water, and the toxicsubstances from the blood to the dialysis solution through theperitoneum. It should also be nontoxic and biologically inert, whilebeing metabolizable by the body, a portion thereof being assimilated inthe blood. It should not cross the peritoneal membrane too rapidly, soas to durably maintain an ultrafiltration gradient without accumulatingundesirable substances in the blood.

In its EP patent 667,356, the Applicant Company proposed a method formanufacturing, from waxy starch, a starch hydrolyzate which iscompletely soluble in water and which has a low polydispersity value ofless than 2.8, and a Mw of between 5×10³ and 1×10⁶ daltons.

This method consists in hydrolyzing, by an acid route, a starch milkconsisting exclusively of amylopectin, and then in supplementing thisacid hydrolysis with an enzymatic hydrolysis using a bacterialα-amylase, and chromatographing on macroporous strong cationic resins inalkali or alkaline-earth metal form.

It should be noted that at the time, the Applicant Company recommendedusing only starches almost exclusively composed of amylopectin andcommonly called waxy starches as raw material in said method, thestarches containing a non-negligible proportion of amylose not beingsuitable.

This starch hydrolyzate, also called icodextrin, allowed a significantreduction in the daily absorption of glucose previously used as osmoticagent in dialysis solutions, thus constituting a potential advantage forthe treatment of diabetic and obese patients for whom the calorie supplyis a critical factor. This could however be further improved by using anosmotic agent which is less glycemic, and whose osmotic power would lastlonger, which would make it possible to significantly lighten thedialysis treatment procedure. Indeed, having improved the yield ofdialyzates, the rate at which the dialysis bags are changed would bereduced, which constitutes a definite improvement in the patient'squality of life.

Thus, the ideal carbohydrate in peritoneal dialysis should:

-   -   be soluble in water    -   exert osmotic pressure    -   have a low viscosity    -   not undergo retrogradation    -   induce low kinetics of appearance of glucose in the system        circulation    -   be slowly hydrolyzed by amylase so as to exert a lasting osmotic        pressure.

Indeed, in relation to the latter point, the fate of the osmotic agentsadministered in solution into the peritoneal cavity in renalinsufficiency sufferers is determined by its stability in the peritonealfluid, the degree of absorption in the system circulation and the rateof hydrolysis by amylase. However, the prior art osmotic agents have thedisadvantage of being rapidly hydrolyzed.

Likewise, so-called resistant starches have been proposed as glycemiaregulating agents. However, these are generally not stable in thecompositions, cannot be sterilized, which ultimately causes a loss ofproduct, and they can be fermented and do not therefore supply theexpected amount of calorie.

From the preceding text, it is evident that an unsatisfied needtherefore exists to have glucose polymers which exhibit remarkableproperties, in particular in terms of stability, solubility and possiblyviscosity, and which thereby confer on the products containing themhigher capacities of shelf life, controlled digestibility, which allowsthe use thereof in fields as varied as peritoneal dialysis, enteral orparenteral nutrition, as glycemia inhibitor and/or regulator, as energysupply during physical activities and as digestion regulator.

The Applicant Company has had the merit of reconciling all theseobjectives which were up until now reputed difficult to reconcile, bydevising and producing, at the cost of numerous research studies, novelsoluble highly branched glucose polymers.

The soluble highly branched glucose polymers in accordance with theinvention, which have a reducing sugar content of less than 1%, are thuscharacterized in that they possess a level of α-1,6 glucoside bondsgreater than 10%, preferably of between 12 and 30%, a Mw, determined bylight scattering, having a value of between 0.3×10⁵ and 2×10⁵ daltons,and an osmolality, determined according to a test A, having a value ofbetween 1 and 15 mOsm/kg.

The soluble branched glucose polymers in accordance with the inventionhave a low reducing sugar content.

The determination of the reducing power of the branched glucose polymersin accordance with the invention, by any method moreover known to aperson skilled in the art, leads to values below 1%.

The level of α-1,6 glucoside bonds in the soluble branched glucosepolymers in accordance with the invention is determined by proton NMRanalysis. The level of branching is then expressed in percent,corresponding to the quantity of proton signal carried by the C1 of ananhydroglucose unit which binds another anhydroglucose unit by an α-1,6bond, when a value of 100 has been given to all the signals of theprotons carried by all the C1 atoms of the glucose residues of saidsoluble glucose polymers.

Under these conditions, it is determined that the soluble highlybranched glucose polymers in accordance with the invention have acontent of α-1,6 bonds which is greater than 10%, preferably of between12% and 30%.

This content of α-1,6 bonds confers on any highly branched glucosepolymer in accordance with the invention a particular structure, interms of branching and/or length of branched chains in relation to thestarch or to the starch derivative from which it is derived.

This particularly high content of α-1,6 glucoside bonds makes the highlybranched glucose polymers according to the invention difficult todigest, which contributes to their being able to be used as digestionregulating agent and as glycemia inhibiting agent, as stated above.

They can therefore be usefully offered to diabetics or to predisposedsubjects as foods, drinks or nutritional aids which have the role ofinhibiting the increase in glycemia.

The soluble highly branched glucose polymers in accordance with theinvention also exhibit the absence of retrogradation in aqueous solutionand a remarkable stability.

This property makes the branched glucose polymers in accordance with theinvention most naturally destined for compositions which can be used inthe food industry, which thereby exhibit high stabilities duringstorage.

Another advantage of the invention is to allow the production of afinished product which can be used for example as an instant binder inrefrigerated or deep-frozen products.

The determination of the molecular masses of the soluble branchedglucose polymers in accordance with the invention is carried out bymeasuring the weight-average molecular masses (Mw).

This value is obtained by steric exclusion chromatography on PSS SUPREMA100 and PSS SUPREMA 1000 columns mounted in series and coupled to alight scattering detector.

The branched glucose polymers in accordance with the invention therebyhave a Mw value of between 0.3×10⁵ and 2×10⁵ daltons.

The soluble glucose polymers in accordance with the invention also havea remarkably low osmolality.

The test A consists in determining the osmolality of a solutioncontaining 100 g on a dry basis of highly branched glucose polymers inaccordance with the invention placed in 1 kg of water.

The measurement of the osmolality of this solution is then carried outon a FISKE® ASSOCIATES MARK 3 osmometer, following the manufacturer'sspecifications.

The branched glucose polymers in accordance with the invention therebyhave a remarkably low osmolality value of between 1 and 15 mOsm/kg.

No glucose polymer exists, to the knowledge of the Applicant Company,which possesses such an osmolality value, for products which moreoverhave a level of branching and molecular weight as defined.

Indeed, comparative measurements carried out on conventionalmaltodextrins having a dextrose equivalent (DE) of between 5 and 20 showosmolality values of between 25 and 85 mOsm/kg.

Other measurements, performed on limit dextrins as defined above bytreating starch liquefied with α-amylase, which are marketed under thename BLD 8 by SANMATSU, give for a molecular weight of between 0.4 and0.5×10⁵ daltons and an α-1,6 branching content of between 8 and 9%, anosmolality value of more than 35 mOsm/kg.

This very low osmolality value thus confers on the highly branchedsoluble polymers in accordance with the invention properties which allowthem to be used in preparations intended for athletes, to replace theenergy sources which they need for physical efforts over long periods.

However, these compositions can also and in particular be advantageouslyused for patients who can no longer take in food normally, in thecontext of enteral and parenteral nutrition.

Moreover, combined with this property of low osmolality, their lack ofretrogradation, their molecular weight profile and their lowpolydispersity value makes these highly branched glucose polymers inaccordance with the invention perfect candidates as osmotic agents forapplications in peritoneal dialysis, as will be exemplified below. TheApplicant has moreover demonstrated that these polymers in accordancewith the invention have a resistance to alpha-amylase which providessignificant advantages compared with the prior art polymers, for asimilar molecular weight, since they are less glycemic and have anosmotic power which lasts longer, thus allowing their use in longdialysis treatments.

Advantageously, the highly branched glucose polymers in accordance withthe invention may be classified into three subfamilies according totheir osmolality.

The first subfamily covers the highly branched polymers which have, fora Mw determined by light scattering having a value of between 0.5×10⁵and 1.5×10⁵ daltons, an osmolality, determined according to the test A,at least equal to 1 and less than 2 mOsm/kg.

The second subfamily covers highly branched polymers which have, for aMw determined by light scattering having a value of between 0.5×10⁵ and0.8×10⁵ daltons, an osmolality, determined according to the test A, atleast equal to 2 and less than 5 mOsm/kg.

The Applicant Company has additionally found branched glucose polymersbelonging to the two subfamilies which further have a remarkably highα-1,6 branching level, i.e. of between 15 and 30%.

The third subfamily covers highly branched polymers which have a Mwdetermined by light scattering of between 0.3×10⁵ and 0.7×10⁵ daltonsand an osmolality, determined according to the test A, at least equal to5 and less than 15 mOsm/kg.

To prepare the soluble branched glucose polymers in accordance with theinvention, the following succession of steps are carried out whichconsist in:

-   a. preparing an aqueous starch suspension or a solution of starch    derivative having a dry matter content at least equal to 1% by    weight, preferably from 10 to 50% by weight,-   b. treating said suspension or said solution with at least one    branching enzyme at a temperature between 25 and 80° C. for a period    of 1 to 24 hours,-   c. causing at least one enzyme chosen from the group consisting of    α-amylase, β-amylase, amyloglucosidase and α-transglucosidase to act    on the suspension or on the solution thus obtained,-   d. carrying out a fractionation using at least one technique chosen    from the group comprising membrane separations or chromatographies,    so as to recover the high molecular weight fractions,-   e. collecting the branched glucose polymers thus obtained.

The starch is introduced in suspension, or the starch derivatives inaqueous solution, at a dry matter content at least equal to 1% byweight, preferably from 10 to 50% by weight.

The choice of a source, or of a quality of starch or of its particularderivatives, is only of a relative importance.

In fact, the Applicant Company has developed a novel method, which makesit possible to obtain the highly branched glucose polymers in accordancewith the invention, for example which are applicable in peritonealdialysis, which does not require being limited to a particular type ofstarch, in this case a starch rich in amylopectin.

It is therefore possible to choose the natural or hybrid starch obtainedfrom potato, potato with a high content of amylopectin (waxy starch),pea, rice, cassava, wheat, corn, corn or wheat rich in amylopectin (waxycorn or wheat), corn with a high content of amylose, cuts or fractionswhich can be made or obtained from starches, such as amylose,amylopectin, particle size fractions known to persons skilled in the artby the terms wheat starch “A” and wheat starch “B”, and mixtures of atleast any two of the abovementioned products.

The starch derivatives may be understood to mean modified starchesobtained from enzymatic, chemical and/or physical modification, in oneor more steps, of this starch.

The starch derivatives may be in particular starches modified by atleast one of the known techniques of esterification, etherification,crosslinking, oxidation, alkaline treatment, acid and/or enzymatichydrolysis (responsible for the maltodextrins and dextrins).

The Applicant Company has found that the highly, branched glucosepolymers in accordance with the invention can be easily synthesized fromstarches, or from their derivatives, which already have a branchinglevel at least equal to 1%.

This starch suspension, or this solution of starch derivatives, may thenbe optionally subjected to a particular cooking treatment, whichconsists in treating it at a temperature of greater than 130° C.,preferably of between 140 and 150° C., at a pressure of more than 3.5bar, preferably of between 4 and 5 bar, for 30 seconds to 15 minutes,preferably for 1 to 5 minutes.

This treatment is advantageously carried out in a jacketed tubularcooker heated by a thermal fluid, which equipment can be easily obtainedby persons skilled in the art.

The second step of the method in accordance with the invention consistsin treating said starch suspension or said solution of starch derivativewith a branching enzyme.

Advantageously, 50 000 to 500 000 U of purified branching enzyme areused per 100 g on a dry basis of starch or of starch derivative, at atemperature of between 25 and 95° C., preferably at a temperature ofbetween 70 and 95° C., for a period of 1 to 24 hours.

The expression branching enzymes is understood to mean, for the purposesof the invention, the branching enzymes chosen from the group consistingof glycogen branching enzymes, starch branching enzymes and any mixturesof these enzymes.

More particularly, these branching enzymes are extracted from organismsand/or microorganisms chosen from the group consisting of glycogenbranching enzymes, starch branching enzymes and any mixtures of theseenzymes.

The Applicant Company prefers, in order to carry out this treatment witha branching enzyme, to follow the teaching of its patent application WO00/18,893.

This step leads to the production of soluble branched glucose polymers,but with a content of α-1,6 glucoside bonds at best equal to 10%.

To increase this value and to reach levels of α-1,6 bonds of up to 30%,the Applicant Company found that it is necessary to carry out anadditional enzymatic treatment, and that is what constitutes the thirdstep of the method for producing the soluble highly branched glucosepolymers in accordance with the invention.

This third step consists in causing at least one enzyme chosen from thegroup consisting of α-amylase, β-amylase, amyloglucosidase andα-transglucosidase to act on the suspension or the solution treated witha branching enzyme thus obtained.

The conditions for action (temperature and pH) of the different enzymesused in the method in accordance with the invention are chosen from thefollowing (the quantities are determined in relation to the substrateconsidered, as will be exemplified below):

-   α-amylase: of the LYSASE 2000 type from GENENCOR, at a temperature    of 55 to 65° C., pH of 6.5 to 6.7, for 30 minutes to 1 hour;-   β-amylase: of the SPEZYME BBA type from GENENCOR, at a temperature    of 40° C., pH of 4.9 to 5, for 1 h 30 min to 2 hours;-   amyloglucosidase: either of the OPTIDEX L300 A type from GENENCOR at    a temperature of 55° C., pH of 4.7, or of the A-7420 type from SIGMA    at a temperature of 50° C. to 60° C., pH from 4.7 to 4.9; for 1 h 30    min to 2 hours;-   α-transglucosidase: of the α-TGase type from L-AMANO at a    temperature of 55° C., pH from 5 to 5.2, for 1 hour.

The enzymes used may be of bacterial or fungal origin.

At the end of this additional treatment, the soluble highly branchedglucose polymers are obtained in the form of a mixture with theirproducts of enzymatic degradation, predominantly consisting of glucose,maltose and/or isomaltose, as will be exemplified below.

The fourth step of the method consists in carrying out a fractionationusing a technique chosen from the group comprising membrane separationsand chromatographies, so as to recover the high molecular weightfractions and the low molecular weight fractions.

The high molecular weight fractions correspond to the highly branchedglucose polymers in accordance with the invention, while the lowmolecular weight fractions make it possible to obtain, with an excellentyield, compositions rich in maltose and/or isomaltose.

Advantageously, a fractionation technique is chosen from the groupconsisting of the ultrafiltration membrane separation technique and bythe chromatographic separation technique on a gel type support.

In a first embodiment of this fourth step of the method, thefractionation is performed using an ultrafiltration membrane separationtechnique, using a membrane having a cut-off at least equal to 3000daltons, preferably at least equal to 5000 daltons.

The high molecular weight fractions corresponding to the highly branchedglucose polymers, equal to the ultrafiltration retentate, then representabout 60% of the dry matter content used.

In a second embodiment of this fourth step of the method, thefractionation is performed using a chromatograpy technique carried outon a gel type resin.

The profiles obtained allow the separation of the fractions containingthe highly branched glucose polymers with an optimum yield of between 40and 45%.

Regardless of the method used, the profiles obtained allow theseparation of the high molecular weight polysaccharide fractioncorresponding to the soluble branched glucose polymers in accordancewith the invention, from the low molecular weight oligosaccharidefractions essentially consisting of glucose and maltose and/orisomaltose.

The last step of the method in accordance with the invention thereforeconsists in collecting on the one hand the high molecular weightfractions corresponding to the highly branched glucose polymers, and onthe other hand the low molecular weight fractions enriched with glucoseand isomaltose and/or with maltose.

The high molecular weight products may be combined as they are, orprecipitated with 3 volumes of ethanol, purified and dried under vacuumfor 24 hours, or alternatively spray-dried, by any technique known to aperson skilled in the art.

As for the compositions enriched with maltose and/or isomaltose,characterized in that they comprise the low molecular weight fractionsof step d of the method in accordance with the invention, they may beused as they are, or hydrogenated by any hydrogenation techniquemoreover known to a person skilled in the art.

The particular physicochemical characteristics of the polymers accordingto the invention allow their applications in industry in particular thePaper-Carton, Textiles, Cosmetics, and particularly Pharmaceutical andFood industries, and still more particularly in the fields of enteraland parenteral nutrition, peritoneal dialysis as an osmotic agent, as aglycemia inhibiting agent, as an energy source during physicalactivities and as a digestion regulating agent.

As regards the particular field of peritoneal dialysis, the applicanthas found, using a test of resistance to alpha-amylase, that a family ofpolymers in accordance with the invention was particularly suited to thepreparation of solutions for peritoneal dialysis, as will be exemplifiedlater. These polymers are used therein as an osmotic agent.

The invention thus relates to a composition for peritoneal dialysis,characterized in that it comprises, as osmotic agent, at least onesoluble highly branched polymer having a reducing sugar content of lessthan 1%, and having:

-   a content of α-1,6 glucoside bonds greater than 8%, preferably of    between 10 and 30%,-   a Mw, determined by light scattering, having a value of between    0.3×10⁵ and 2×10⁵ daltons,-   an osmolality, determined according to a test A, having a value of    between 1 and 15 mOsm/kg.

According to a preferred variant of the invention, said polymer has:

-   a Mw, determined by light scattering, having a value of between    0.3×10⁵ and 0.7×10⁵ daltons,-   an osmolality, determined according to a test A, at least equal to 5    and less than 15 mOsm/kg.

The composition for peritoneal dialysis according to the invention mayadditionally comprise physiologically acceptable electrolytes, such assodium, potassium, calcium, magnesium, chlorine, so as to avoid lossthrough transfer of electrolytes from the serum to the peritoneum.

This composition may be provided in solid form for preparationimmediately before use or in liquid form, for example as an aqueoussolution. In the latter case, the solution obtained by dissolving thehighly branched polymers according to the invention in water should beclear and colorless. This solution should be preferably free ofendotoxins, of peptidoglucans and of beta-glucans, and of nitrogenouscontaminants resulting from the raw material, or from the enzymaticpreparations used for its manufacture.

To this effect, the highly branched polymers used in said solution wouldhave preferably been subjected to purification so as to remove any coloror any undesirable contaminant such as proteins, bacteria, bacterialtoxins, fibers, traces of metals, and the like.

This purification step may be carried out according to techniques knownto the person skilled in the art.

The dialysis solution according to the invention may also comprisebuffer solutions (lactate, acetate, gluconates in particular) and otheradditives such as amino acids, insulin, polyols such as for examplesorbitol, erythritol, mannitol, maltitol and xylitol.

The addition of polyols to the composition, and preferably of polyolswhich are a pyrogenic and free of the impurities described above(endotoxins and other residues of bacterial origin in particular) makesit possible to increase the osmolarity of the solution moreadvantageously than glucose or maltose, because of their lower calorificvalue, their higher osmotic power and because they are not reducing.

The dialysis composition according to the invention is advantageouscompared with the prior art products since the osmotic agent which itcontains makes it possible to exert a lasting osmotic pressure andinduces a low kinetics of appearance of glucose, while being stable toretrogradation, thus satisfying the principal criteria defined above.

Other characteristics and advantages of the invention will emerge onreading the nonlimiting examples described below.

EXAMPLE 1

A solution of starch derivatives having a dry matter content of 25% byweight is prepared by heating to 80° C., with slow and continuousstirring.

Two maltodextrins marketed by the Applicant Company under the namesGLUCIDEX® 2 (substrate A) and GLUCIDEX® 6 (substrate B) at 250 g/l areused in this case.

This solution is cooled to 30° C., and the pH is brought to 6.8 with 1 NNaOH.

These solutions are then treated with purified glycogen branching enzymeextracted from the microorganism B. stearothermophilus.

The branching enzyme is added in an amount of 1600 U/g of substrate, andthe temperature is gradually brought to 65° C.

The incubation is carried out with moderate stirring for 4 hours. Thereaction is then stopped by reducing the pH to a value of 5 and byboiling for 6 minutes.

Table I below assembles, for both substrates tested, the resultsobtained in terms of contents of α-1,6 glucoside bonds, Mw values,reducing sugar contents and osmolality for the products obtained(product C from the substrate A and product D from the substrate B).

TABLE 1 % of α-1,6 Mw % of reducing Osmolality bonds 10⁵ daltons sugarsmOsm/kg A 5.9 4.88 2 16 B 8.7 1.19 1.5 12 C 5.4 0.9 3.8 25 D 8 0.61 4.325

The content of α-1,6 glucoside bonds is substantially increased, but isnot yet up to the desired values.

The Applicant Company found that an additional treatment should becarried out, by the action of enzymes which specifically hydrolyze theα-1,4 glucoside bonds (such as α-amylase, β-amylase oramyloglucosidase), or by the use of enzymes which complete the branchinginto α-1,6 bonds (such as α-transglucosidase), this being in thefollowing manner.

For the additional enzymatic treatments, the solutions of the branchedmaltodextrins C and D are first of all brought to the temperature andthe pH for the chosen enzyme.

1) For the additional treatment with α-amylase (LYSASE 2000 to 2444BRU/g of enzymatic extract), said solutions of C or D are brought to atemperature of 60° C. and to a pH of 6.5 to 6.7, and 6 U of α-amylaseare added per g of substrate.

The incubation is carried out for 30 minutes, and the reaction isstopped by boiling for 6 minutes.

2) For the additional treatment with β-amylase (BBA SPEZYME fromGENENCOR), said solutions of C or D are brought to the temperature of40° C. and to the pH of 4.9 to 5, and 30 U of β-amylase are added per gof substrate.

The incubation is carried out for 2 hours, and the reaction is stoppedby boiling for 6 minutes.

3) For the additional treatment with amyloglucosidase (A. niger AMG fromSIGMA AA-7420, at 40 U/mg of proteins), said solutions of C or D arebrought to the temperature of 55° C. and to the pH of 4.7 to 4.9, and 20U of AMG are added per g of substrate.

The incubation is carried out with moderate stirring for 2 hours, andthe reaction is stopped by boiling for 6 minutes.

4) For the additional treatment with α-transglucosidase (L-AMANOα-TGase, activity of 27.7 μmol of glucose), said solutions of C or D arebrought to the temperature of 55° C. and to the pH of 5 to 5.2, and 2 Uof α-TGase are added per g of substrate.

The incubation is carried out for 1 hour, and the reaction is stopped byboiling for 6 minutes.

The physicochemical characteristics:

-   of the products E and F (obtained by additional treatment with    α-amylase of the products C and D respectively),-   of the products G and H (obtained by additional treatment with    β-amylase of the products C and D respectively),-   of the products I and J (obtained by additional treatment with AMG    of the products C and D respectively) and-   of the products K and L (obtained by additional treatment with    α-TGase of the products C and D respectively)    are then determined.

TABLE II % of α-1,6 Mw % of reducing Osmolality bonds 10⁵ daltons sugarsmOsm/kg E 8.3 0.72 3.8 29 G 8.4 0.76 22.5 132 I 9 0.49 55 320 K 9.6 1.222 153 F 7.4 0.44 8.7 52 H 7.2 0.51 23.8 141 J 7.8 0.47 50.5 301 L 120.69 28 192

The osmolality and the reducing sugar content which increase, indicatehere the concomitant production mainly of glucose, of DP2 (maltose andisomaltose), which therefore has to be removed in order to obtain thehighly branched glucose polymers in accordance with the invention.

It is chosen to use a fractionation by ultrafiltration on membrane witha cut-off of 5000 daltons (AMICON 5K membrane).

The results obtained for the products of ultrafiltration M, O, Q, S ofthe compounds E, G, I and K, respectively, on the one hand (which aretherefore derived from GLUCIDEX® 2), and the products of ultrafiltrationN, P, R, T of the compounds F, H, J and L, respectively, (which aretherefore derived from GLUCIDEX® 6), are presented in the followingTable III.

TABLE III % of α-1,6 Mw % of reducing Osmolality bonds 10⁵ daltonssugars mOsm/kg M 10.2 0.89 0.42 1 O 15 0.75 0.3 1 Q 18.8 0.57 0.37 2 S12.1 1.22 0.33 1 N 10.9 0.69 0.54 2 P 14.4 0.51 0.8 3 R 18.1 0.55 0.5 5T 12.2 0.72 0.6 3

These results indicate the fact that the highly branched glucosepolymers thus obtained exhibit the perfect equilibrium between theremarkably high (up to 18%) level of α-1,6 glucoside bonds, for productswhich have such a Mw value value and such a low osmolality value.

These highly branched glucose polymers can be easily mixed with otherelectrolytes to provide osmotic agents which are extremely efficient inperitoneal dialysis, or can be used as they are in compositions intendedfor regulating digestion, for parenteral and enteral nutrition, forcompositions intended for diabetics, or in liquid drinks in order toreconstitute the energy reserves for athletes during a long physicaleffort.

It should be noted that in addition to these highly branched glucosepolymers, the method also makes it possible to group together thefractions rich in maltose and/or isomaltose.

For example, in the case of the preparation of the products S and T(obtained from the combined treatment with the branching enzyme and withα-TGase), isomaltose and glucose are the sole coproducts manufactured(at the respective concentrations of 25 to 30 g/l and 75 to 80 g/l.

Likewise, in the case of the preparation of the products O and P(obtained from the combined treatment with the branching enzyme andβ-amylase), maltose is the only coproduct manufactured (at theconcentration of 130 g/l).

These low molecular weight fractions may therefore constituteadvantageous sources of compositions rich in maltose and/or isomaltose.

EXAMPLE 2

The highly branched glucose polymers in accordance with the inventionmay also be prepared from standard corn starch. For this, 110 g on a drybasis of starch are suspended in one liter of water at room temperatureand with slow and continuous stirring.

The pH is brought from 6.8 to 7 and the medium is left under theseconditions for 15 minutes, adjusting the pH if necessary. The glycogenbranching enzyme purified from B. stearothermophilus is added in anamount of 4000 U/g of substrate, the temperature being gradually broughtto 72 to 75° C.

The incubation is then carried out with moderate stirring for 30minutes, followed by cooling to a temperature of 65 to 68° C. Theenzymatic reaction is carried out for 4 hours. The reaction is thenstopped by reducing the pH to a value of 4.5 to 5, the medium is heatedat boiling temperature for 6 minutes.

As in Example 1, the reaction is supplemented by treatments withβ-amylase or with amyloglucosidase, and then by a step ofultrafiltration on a membrane with a cut-off of 5000 daltons under theconditions given in Example 1.

Table IV groups together the results obtained.

The standard corn starch is designated by the reference U; the productof treatment with the branching enzyme V, those additionally treatedwith β-amylase: W, with AMG: X; the ultrafiltered final products: Y andZ.

TABLE IV % of α-1,6 Mw % of reducing Osmolality bonds 10⁵ daltons sugarsmOsm/kg U 3.6 110 <0.01 Nd V 8.8 1.75 0.2 2 W 8.9 1.31 20.5 117 Y 16.31.38 0.1 2 X 7.9 0.55 55 357 Z 24.2 0.45 0.4 2

The products Y and Z obtained exhibit the same balanced profiles asthose described in Example 1, and can therefore be advantageously usedin the same fields of application.

EXAMPLE 3

Two other highly branched glucose polymers are prepared from twovarieties of starch rich in amylopectin, under industrial conditions.They are two samples of acidic fluidified waxy corn starch with a levelof fluidification WF of about 90, also marketed by the Applicant Companyunder the trade name CLEARGUM® CB 90.

Table V presents the operating conditions used to obtain the highlybranched glucose polymers in accordance with the invention.

TABLE V Base CLEARGUM CB90 CLEARGUM CB90 Solubilization Continuouslaboratory Continuous laboratory cooker containing cooker containing 25%DM 25% DM 1st enzyme Branching enzyme Branching enzyme 50 000 U/ml - 1ml/100 g 50 000 U/ml - 1 ml/100 g dry basis dry basis 1st enzymatic 70°C. pH 6.8 22 h 70° C. pH 6.8 22 h treatment and then deactivation andthen deactivation 1 h at 90–95° C. 1 h at 90–95° C. 2nd enzymeAmyloglucosidase β-amylase OPTIDEX L300A SPEZYME BBA 0.08 ml/100 g drybasis + 0.2 ml/100 g dry basis 0.08 ml/100 g dry basis after 1 h 30 min2nd enzymatic 55° C. pH 4.7 - 2 h 40° C. pH 5 2 h treatment and 3 h andthen and then deactivation deactivation 1 h at 1 h at 90–95° C. 90–95°C. Purification Filtration on 8 and Adjustment of pH to then 0.22 μm -membrane 3.5 over 18 h - ultrafiltration Centrifugation 5000 rpm PCIMembrane Systems 10 min - Filtration on ES209 (9000 Da) - filteringearth and Charcoal treatment then 8 μm - Membrane NORIT SX+ 5% dryultrafiltration basis pH 5 70° C. 1 h - PCI Membrane Systems adjustmentof pH to ES209 (9000 Da) - 5.8 and filtration on Charcoal treatment 8and then 0.22 μm NORIT SX+ 5% dry basis pH 5 70° C. 1 h - Filtration on8 and then 0.22 μm Recovery Concentration to dryness Concentration todryness in a rotary evaporator in a rotary evaporator under vacuum undervacuum

Table VI presents the results obtained in terms of content of α-1,6glucoside bonds, of Mw values, of reducing sugar contents and ofosmolality for the products obtained:

-   “a” relates to the product obtained from CLEARGUM® CB 90 after    treatment with the branching enzyme and amyloglucosidase and-   “b” relates to the product obtained from CLEARGUM® CB 90, after    treatment with the branching enzyme and β-amylase.

TABLE VI % of α-1,6 Mp % of reducing Osmolality bonds 10⁵ daltons sugarsmOsm/kg “a” 19.4 0.33 1 12 “b” 14.3 0.68 0.7 6

These results indeed show that the method used makes it possible toobtain highly branched glucose polymers in accordance with the inventionregardless of the starch or starch derivative base chosen.

EXAMPLE 4

Aqueous solutions of highly branched polymers in accordance with theinvention are prepared, and they are brought into contact with anamylase of pancreatic origin. The amylase hydrolysis is monitored overtime by measuring the reducing sugars formed and by measuring theglucose which appears in the reaction medium. This test makes itpossible to evaluate the resistance of the polymers to amylasehydrolysis, which is an essential criterion in the choice of an osmoticagent for a dialysis solution.

Several polymers in accordance with the invention are tested incomparison with icodextrin (prior art osmotic agent). The polymers arechosen so as to have a molecular weight close to the latter:

Products A and B as prepared in accordance with Example 3 and product Zas prepared in accordance with Example 2.

The icodextrin is manufactured in accordance with patent EP 667,356cited in the description.

A maltose control is prepared in order to validate the in vitro model ofenzymatic digestion.

The operating conditions for the amylase digestion are the following:

-   -   accurately weigh about 0.6 g of product to be tested,    -   add 150 ml of Na maleate buffer pH 7 at 0.1 mol/l,    -   stir until the product dissolves,    -   remove 1.5 ml of the solution obtained (initial solution=si),    -   place the bottles on a water bath for 15 minutes, so that the        temperature of the solution is 37° C.,    -   add 0.15 g of pig pancreatin (α-amylase of animal origin),    -   incubate at 37° C. on a thermostated bath, with stirring, for        300 minutes RT,    -   collect samples of 1.5 ml at the times: 15, 30, 45, 60, 90, 120,        180, 240, 300 minutes,    -   stop the enzymatic reaction by placing the samples in a bath to        dryness at 100° C. for 10 minutes,    -   assay the glucose on the samples, in order to simulate the        impact of the studied product on glycemia,    -   assay the reducing sugars on the samples in order to study the        rate of hydrolysis.

For the glucose assay, a colormetric method is used which is carried outon a HITACHI 704 automatic machine (ROCHE). The reagent used is areagent containing the enzymes GOD/PAP (glucose oxidase/peroxidase). Thevolume of reagent used is 500 microliters, the sample volume is 5microliters and the reaction temperature is 30° C.

The method used for the assaying of reducing sugars is the SOMOGYINELSON method. 200 microliters of sample are introduced into a stopperedtube, and 200 microliters of working solution (sodium tartrate andcopper sulfate reagents) are added. The medium is heated to boilingtemperature, and the arsenomolybdic reagent is added after cooling,followed by water. The solution obtained is deposited in a microplate,and then the absorbence is read using a microplate reader at awavelength of 520 nanometers.

The results are presented in the following tables:

1. Kinetics of appearance of glucose (as % released on a dry basis) Time(in min) MALTOSE A B Z ICODEXTRIN si 0.26 3.35 0.00 0.53 0.28 0 0.264.75 0.93 1.19 1.96 15 0.79 5.31 1.59 — 3.07 30 1.06 5.68 1.96 2.11 3.6345 1.59 5.86 2.24 — 3.91 60 2.12 6.14 2.52 2.37 4.19 90 2.65 6.52 2.89 —4.75 120 3.44 6.61 3.17 2.90 5.31 180 5.03 7.26 4.76 3.43 6.15 240 6.358.10 — 3.96 6.99 300 7.68 8.38 5.41 4.22 7.82

2. Kinetics of appearance of the reducing sugars (as % on a dry basis)Time (in min) MALTOSE A B Z ICODEXTRIN si 51.01 5.76 0.88 1.45 2.74 049.82 18.34 18.04 8.92 31.07 15 47.94 19.33 18.96 — 30.39 30 48.29 20.0019.04 11.00 32.53 45 48.55 20.25 19.78 — 32.46 60 48.84 19.92 20.8011.10 32.95 90 49.42 20.37 19.42 — 34.16 120 47.15 21.68 21.04 12.1634.40 180 48.87 22.46 21.79 12.22 36.64 240 50.90 23.05 23.11 12.2937.03 300 52.20 22.67 22.88 13.64 37.06

3. Summary analysis of the results % of % of reducing glucose sugarsContent of PRODUCTS released at formed at α-1,6 bonds Molar mass TESTED300 min 300 min in % (daltons) MALTOSE 7.41 52.20 0   342 A 5.03 16.9119.4 33 000 B 5.41 22.88 14.3 68 000 Z 3.69 12.19 24.2 45 000 ICODEXTRIN7.54 34.32 6.5–8 12 000–20 000

It is observed from the results obtained that the higher the level ofbranching (the level of α-1,6 bonds), the lower the amylase hydrolysis.

The latter is generally dependent on the molecular weight. Thus, thehigher the level of branching and the lower the molecular weight, theless the molecule is attacked by amylase.

For a use in intraperitoneal dialysis, the products A and Z areparticularly suitable and have a resistance which is markedly higherthan icodextrin, which means that these products have a definiteadvantage in terms of duration of osmotic power and of glycemic power,for a similar molecular weight.

EXAMPLE 5

Aqueous solutions of highly branched polymers in accordance with theinvention are prepared, and they are brought into contact with anamylase of pancreatic origin and with an intestinal amyloglucosidase(acetonic intestine powder). The hydrolysis is monitored over time bymeasuring the glucose which appears in the reaction medium. This testmakes it possible to evaluate the resistance of the polymers tohydrolysis by the enzymes involved in the digestion of foodcarbohydrates, which is an essential criterion in the choice of a foodingredient entering into the composition of formulations for use byathletes or intended for enteral and parenteral nutrition.

Several polymers in accordance with the invention are tested incomparison with icodextrin, glycogen, and a standard maltodextrin. Thepolymers chosen are the following:

Products A are prepared in accordance with Example 3, products Y areprepared in accordance with Example 2, and products Y′ preparedaccording to Example 2 from an amylopectin-rich starch treated with thebranching enzyme and ultrafiltered.

The icodextrin is manufactured in accordance with patent EP 667.356cited in the description. The glycogen is a bovine liver glycogenprovided by the company SIGMA-ALDRICH.

A standard maltodextrin control is prepared in order to validate the invitro model of enzymatic digestion.

-   -   The operating conditions for the enzymatic digestion are the        following:    -   Accurately weigh about 0.6 g of product to be tested.    -   Add 150 ml of Na maleate buffer pH 7 at 0.1 mol/l.    -   Stir until the product dissolves.    -   Remove 1.5 ml of the solution obtained.    -   Place the bottles on a water bath for 15 minutes, so that the        temperature of the solution is 37° C.    -   Add 0.15 g of pig pancreatin.    -   Incubate at 37° C. on a thermostated bath, with stirring, for 30        minutes RT.    -   Collect samples of 1.5 ml at the times: 0 min at 30 minutes.    -   Stop the enzymatic reaction by placing the samples in a bath to        dryness at 100° C. for 10 minutes.    -   Add 0.15 g of rat intestinal mucous membrane.    -   Incubate for 5 h 30 min at 37° C. on a thermostated water bath,        with stirring.    -   Collect 1.5 ml samples every 60 minutes at the times 60; 120;        180; 240; 300; 330 and 360 minutes.    -   Stop the enzymatic reaction by placing the samples in a bath to        dryness at 100° C. for 10 minutes.    -   Assay the glucose on the samples in order to calculate the        percentage hydrolysis of the product studied.    -   For the glucose assay, the same method as in Example 4 is used.    -   The results are presented in the tables below:

1. Kinetics of appearance of glucose (in % released on a dry basis) TimeStandard (in min) MALTOD. GLYCOGEN A Y Y′ ICODEXTRIN Pancreatic 0 0 0 00 0 0 amylase 15 0.79 2.87 2.61 2.17 3.90 3.35 30 1.06 3.30 2.70 2.714.74 3.63 Intestinal 60 20.88 12.62 9.77 13.71 16.31 15.09 amylase 9038.59 22.81 16.66 23.34 28.29 26.96 120 52.07 31.41 23.17 32.17 40.2837.86 150 62.90 39.45 28.66 39.22 48.64 47.22 180 70.83 46.04 32.7544.52 57.84 55.88 210 78.76 51.50 37.03 49.00 64.53 63.01 240 83.7856.09 39.64 52.39 68.71 69.01 270 88.81 59.96 42.62 54.56 72.33 72.09300 91.18 62.40 45.50 57.27 75.96 76.28 330 93.03 64.26 47.27 58.6379.44 78.37 360 94.36 65.84 51.64 60.80 81.11 80.89

2. Summary analysis of the results % of glucose Level of PRODUCTSreleased at α-1,6 Molar mass TESTED 360 min bonds in % (daltons)STANDARD 94.36 0 3000–5000 MALTODEXTRIN GLYCOGEN 65.84 10 10⁶–10⁷ A51.64 19.4  33 000 Y 60.80 16.3 138 000 Y′ 81.11 7.9 133 000 ICODEXTRIN80.89 6.5–8 12 000–20 000

The maltodextrins according to the invention are particularly suitablefor use in nutrition for athletes or more generally for regulatingglycemia. The products A and Y according to the invention make itpossible to obtain a percentage of release of glucose of between 50 and70%, that is a resistance to hydrolysis which is markedly higher thanconventional maltodextrins and comparable to glycogen, which means thatthese products have a definite advantage in terms of glycemic power andcan thus advantageously constitute a glycogen substitute since theyexhibit similar digestion characteristics.

1. A food composition, comprising soluble highly branched glucosepolymers, said highly branched glucose polymers having a reducing sugarcontent of less than 1%, and wherein said glucose polymers have: acontent of α-1,6 glucoside bonds greater than 10%, a Mw value,determined by light scattering, of between 0.3×10⁵ and 2×10⁵ daltons, anosmolality value, determined according to a test A, of between 1 and 15mOsm/kg.
 2. The food composition according to claim 1, wherein saidglucose polymers have: a Mw value, determined by light scattering, ofbetween 0.5×10⁵ and 1.5×10⁵ daltons, an osmolality, determined accordingto a test A, at least equal to 1 and less than 2 mOsm/kg.
 3. The foodcomposition according to claim 1, wherein said glucose polymers have: aMw value, determined by light scattering, of between 0.5×10⁵ and 0.8×10⁵daltons, an osmolality, determined according to a test A, at least equalto 2 and less that 5 mOsm/kg.
 4. The food composition according to claim1, wherein said glucose polymers have between 12 and 30% of α-1,6glucoside bonds.
 5. The food composition according to claim 1, whereinsaid glucose polymers have between 15 and 30% of α-1,6 glucoside bonds.6. The food composition according to claim 1, wherein said glucosepolymers have: a Mw value, determined by light scattering, of between0.3×10⁵ and 0.7×10⁵ daltons, an osmolality, determined according to atest A, at least equal to 5 and less than 15 mOsm/kg.
 7. The foodcomposition according to claim 1, wherein said composition is a liquid.8. The food composition according to claim 1, wherein said compositionis a solid.
 9. A method for preparing the food composition according toclaim 1, comprising the following steps: preparing an aqueous starchsuspension or a solution of starch derivative having a dry mattercontent at least equal to 1% by weight, treating said suspension or saidsolution with at least one branching enzyme at a temperature comprisedbetween 25 and 80° C. for a period of 1 to 24 hours, adding at least oneenzyme selected from the group consisting of α-amylase, β-amylase,amyloglucosidase and α-transgluscosidase to act on the suspension or onthe solution thus obtained, fractionating by at least one techniqueselected from the group consisting of membrane separations andchromatographies, recovering high molecular weight fractions and lowmolecular fractions, collecting highly branched glucose polymerscorresponding to the high molecular weight fractions obtained, andadding said highly branched glucose polymers to said food product. 10.The method according to claim 9, wherein the branching enzyme isselected from the group consisting of glycogen branching enzymes, starchbranching enzymes and any mixtures of theses enzymes.
 11. The methodaccording to claim 9, wherein the fractionation technique is selectedfrom the group consisting of the technique of separation on anultrafiltration membrane and the technique of chromatographic separationon a gel type support.
 12. The method according to claim 9, wherein thefractionation technique is the technique of chromatographic separationon a gel type support.
 13. An enteral and parenteral nutritioncomposition, comprising the composition according to claim
 1. 14. Aperitoneal dialysis solution, comprising at least one soluble highlybranched polymer according to claim
 1. 15. The dialysis solutionaccording to claim 14, wherein said soluble highly branched polymer has:a Mw value, determined by light scattering, of between 0.3×10⁵ and0.7×10⁵ daltons, an osmolality, determined according to a test A, atleast equal to 5 and less that 15 mOsm/kg.
 16. The solution according toclaim 14, comprising a polyol selected from the group consisting ofsorbitol, mannitol, maltitol, xylitol and erythritol.
 17. The solutionaccording to claim 14, further comprising buffer solutions.
 18. Thesolution according to claim 17, wherein said buffer solution compriseslactate acetate.
 19. The solution according to claim 17, wherein saidbuffer solution comprises gluconate salts.